DOT compliance is not something you deal with once and move on. It’s an ongoing obligation that affects your operating authority, your insurance rates, your ability to win freight contracts, and your legal right to put a truck on the road. If you drive commercially or manage a carrier operation, understanding how the system works — not just that it exists — is the difference between staying compliant and getting caught off guard during a roadside inspection or FMCSA audit.
This guide covers DOT compliance for 2026 in full: the six inspection levels, how CSA scores are calculated, what the 2026 SMS overhaul changed, intervention thresholds by BASIC category, common out-of-service violations, and what you can do to protect your safety record.
What DOT Compliance Actually Covers
When people say “DOT compliance,” they usually mean federal regulations enforced by the FMCSA that govern commercial motor vehicle operations. But it’s useful to be specific about what that includes, because the system has multiple layers.
Registration and authority — having a valid USDOT number, operating authority (MC number) if required, proper insurance filings, and current UCR registration. These are the basic requirements to legally operate as a carrier.
Driver requirements — valid CDL and endorsements for the vehicle being operated, current DOT medical certificate, no prohibited substance violations under the FMCSA Drug and Alcohol Clearinghouse, and compliance with Hours of Service regulations.
Vehicle requirements — meeting FMCSA and CVSA mechanical standards, completing Driver Vehicle Inspection Reports (DVIRs), maintaining proper lights, brakes, tires, and safety equipment, and securing cargo per 49 CFR Part 393.
Records and documentation — maintaining a Driver Qualification File for each driver, keeping drug testing records, retaining DVIR logs, and making records available during inspections and audits.
All of this feeds into a single compliance tracking system: the FMCSA Safety Measurement System (SMS), which calculates your CSA scores.
What Is a CSA Score and How Is It Calculated?
The Compliance, Safety, Accountability (CSA) program is FMCSA’s method for measuring carrier safety performance. Your CSA score is a percentile ranking — from 0 to 100 — in each of the BASIC categories. Higher is worse. A score of 70 means you perform worse than 70% of carriers with similar inspection exposure.
The SMS calculates scores using data from roadside inspections, crash reports, and compliance review findings over a rolling 24-month window. Violations are weighted by two factors:
Severity weight — how directly the violation relates to crash risk. Under the 2026 SMS overhaul (discussed below), FMCSA consolidated severity weights significantly.
Time weight — more recent violations count more. Violations from 0–12 months ago carry more weight than violations from 13–24 months ago. After 24 months, violations drop out of the calculation entirely.
Your percentile ranking is then compared to other carriers in the same safety event group — carriers with similar numbers of inspections. This peer comparison is what produces your percentile score in each BASIC.
The 2026 FMCSA SMS Overhaul: What Changed
FMCSA published a Federal Register notice in November 2024 announcing the most significant overhaul of the Safety Measurement System since the program launched in 2010. The changes have been phased in through 2025 and 2026, with full implementation expected by mid-2026.
Here is what changed:
Violation code consolidation. Over 950 individual violation codes were consolidated into approximately 116 violation groups. This simplifies how violations are categorized and scored.
Simplified severity weights. The previous severity weight scale of 1–10 has been replaced with a simpler 1-or-2 scale. This reduces the complexity of how individual violations affect your score.
Renamed categories. FMCSA is renaming BASICs to “compliance categories” in the revised methodology, though the substance of what each category measures remains similar.
New Vehicle Maintenance subcategory. A new category called “Vehicle Maintenance: Driver Observed” specifically tracks defects found during driver-conducted pre-trip inspections. Your DVIR quality now has its own dedicated tracking.
Hazardous Materials threshold raised. The intervention threshold for Hazardous Materials Compliance was raised from 80% to 90%, reflecting lower crash correlation data for that category. Segmentation by straight truck vs. combination vehicles was also added.
Shortened data weighting window. The period over which older violations are weighted is being shortened, meaning violations age out of meaningful impact faster.
Carriers can use FMCSA’s Prioritization Preview tool at ai.fmcsa.dot.gov/SMS to see their scores under both old and new methodology. Checking this regularly is one of the most practical things a fleet manager can do.
The Seven BASIC Categories and Intervention Thresholds
Under current SMS methodology, carriers are measured in seven BASIC categories. Intervention thresholds determine when FMCSA takes action:
| BASIC Category | What It Measures | Intervention Threshold |
|---|---|---|
| Unsafe Driving | Speeding, reckless driving, improper lane changes, handheld phone use | 65% |
| Hours of Service Compliance | HOS violations, ELD violations, logbook falsification | 65% |
| Driver Fitness | CDL status, medical certification, driver qualification files | 80% |
| Controlled Substances/Alcohol | Drug and alcohol violations, Clearinghouse flags | 80% |
| Vehicle Maintenance | Brake conditions, tires, lights, mechanical defects | 80% |
| Hazardous Materials Compliance | Placarding, shipping papers, packaging (hazmat carriers only) | 90% (updated 2026) |
| Crash Indicator | Crash rate relative to peer carriers over 24 months | 65% |
Exceeding a threshold does not result in automatic fines. It triggers a sequence: FMCSA sends a warning letter, your vehicles get flagged for priority inspection selection, and if scores remain elevated, FMCSA may initiate an offsite or onsite investigation. That investigation can result in civil penalties or an out-of-service order.
The score range below thresholds matters too. Scores in the 50–64% range for a 65% category, or 70–79% for an 80% category, put you in a caution zone where many freight brokers and shippers begin to pull back from working with you — even without formal FMCSA intervention.
The Six Levels of DOT Roadside Inspection
Roadside inspections are the primary source of data for your CSA scores. Understanding what each level involves helps you prepare drivers and vehicles appropriately.
Level I — North American Standard Inspection
The most comprehensive roadside inspection. Covers both the driver and the vehicle. A Level I inspection typically takes 45–60 minutes and includes:
- Driver license, medical certificate, hours of service records, and drug/alcohol history check
- Review of shipping papers if hauling hazmat
- Complete vehicle inspection: brakes, tires, lights, suspension, coupling devices, cargo securement, fuel system, exhaust system, frame, and steering
Level I is the most common source of out-of-service orders and CSA violations.
Level II — Walk-Around Driver/Vehicle Inspection
Similar to Level I but without going under the vehicle. The officer inspects items visible without crawling under the truck. Slightly less comprehensive than Level I but still covers major vehicle systems and all driver documentation.
Level III — Driver/Credential Inspection
A driver-only inspection. No vehicle inspection is conducted. The officer checks:
- Driver’s license and CDL class/endorsements
- Medical examiner’s certificate
- Hours of service records (paper or ELD)
- Record of duty status
- Alcohol/drug testing documentation
- Required permits and shipping papers
Level IV — Special Study Inspection
A one-time, agency-initiated inspection focused on a specific element being studied. These are data collection events rather than standard enforcement stops.
Level V — Vehicle-Only Inspection
A vehicle inspection conducted without the driver present — for example, when a vehicle is parked at a facility during an inspection of a carrier’s premises. The same vehicle standards apply as in a Level I vehicle inspection.
Level VI — Enhanced NAS Inspection for Radioactive Shipments
Applies specifically to vehicles transporting select radioactive materials. Includes all Level I elements plus additional radiological checks.
Most drivers will encounter Level I, II, or III during their careers. Level I is the highest-stakes because it’s the most comprehensive and generates the most violation data.
Most Common Out-of-Service Violations
Out-of-service (OOS) orders prohibit a driver, vehicle, or both from operating until the violation is corrected. OOS violations also generate significant CSA points in the Vehicle Maintenance and Hours of Service BASICs.
The Commercial Vehicle Safety Alliance (CVSA) publishes OOS criteria used by enforcement officers nationwide. The most common categories:
Brake violations consistently rank as the leading cause of vehicle OOS orders. This includes brake adjustment out of limits, missing brake components, brake lines with damage, and brake system air leaks. Brake adjustment limits are specific to brake type and size — drivers and carriers should know the adjustment limits for the brake types on their equipment.
Tire defects include tread depth below minimums (4/32 inch on steering axle tires, 2/32 on others), sidewall damage, and improper inflation. Steering axle tire issues are weighted heavily because of their direct impact on vehicle control.
Lighting defects — inoperative required lights, particularly brake lights, turn signals, and clearance lights.
Hours of Service violations that result in driver OOS include driving beyond the 11-hour limit, exceeding the 14-hour on-duty window, and failing to have the required 10 consecutive hours off duty. ELD data makes HOS violations easier for officers to identify during inspections.
Missing or expired documentation — no valid medical certificate, CDL operating outside authorized class or endorsements, or no record of duty status when ELD is required.
New Entrant Safety Audit
If your carrier is newly registered with FMCSA, you will be subject to a New Entrant Safety Audit within the first 12 months of receiving your operating authority. This is not optional — it’s a mandatory part of the new entrant program under 49 CFR Part 385.
The audit is typically conducted offsite (remotely) and reviews:
- Driver qualification files for each employed driver
- Drug and alcohol testing program records
- Hours of service records
- Vehicle inspection and maintenance records
- Accident register
- Financial responsibility (insurance) filings
Failing the new entrant audit — or failing to respond to FMCSA’s requests during the audit — results in revocation of your operating authority. FMCSA gives you an opportunity to correct deficiencies and demonstrate compliance, but carriers that ignore the process lose their authority entirely.
The FMCSA new entrant program page provides the current requirements and what documents you need to have ready.
How Inspection Selection Works
Inspections are not random. Officers use several inputs to prioritize which vehicles and carriers to inspect:
CSA score targeting — carriers with BASIC scores approaching or exceeding intervention thresholds are flagged in FMCSA’s inspection selection system. Officers at weigh stations and mobile enforcement units can see your carrier’s risk profile.
Vehicle condition during a stop — equipment that appears poorly maintained, has visible defect indicators (e.g., tire wear patterns, damaged lights), or has a trailer that doesn’t match the tractor triggers closer attention.
Prior inspection history — vehicles and carriers with frequent prior violations are more likely to be pulled in at fixed inspection sites.
Random selection — a portion of inspections are random, particularly at high-volume enforcement sites.
Driver behavior — traffic violations, unsafe driving observed before a stop, or log-of-duty-status irregularities can prompt an inspection from patrol officers.
Understanding these triggers helps carriers focus compliance efforts on the things that most directly affect inspection frequency.
How to Improve a CSA Score
CSA scores can only improve one way: accumulate clean, violation-free inspections and eliminate the behaviors that generate violations. There is no shortcut.
Challenge incorrect data through DataQs. The FMCSA DataQs system at dataqs.fmcsa.dot.gov allows carriers and drivers to challenge inspection data they believe is inaccurate. If a violation was incorrectly recorded or a crash was incorrectly attributed to your carrier, a successful DataQs challenge removes or corrects it from your SMS record. Submit challenges promptly — the sooner they’re resolved, the sooner your score reflects accurate data.
Pre-trip inspection discipline. Most vehicle OOS violations are detectable during a thorough pre-trip inspection. Brake adjustment, tire condition, and lighting defects don’t appear suddenly — they develop over time. A consistent, thorough pre-trip inspection process using your CDL pre-trip checklist catches defects before an enforcement officer does.
HOS compliance training. Reviewing HOS rules with drivers regularly reduces logbook violations. ELD data makes it easy for officers to see patterns — carriers whose drivers consistently push the boundaries of HOS limits will see it reflected in their scores.
Preventive maintenance scheduling. Brake adjustments and tire inspections should be on a regular maintenance calendar, not just done reactively. A written preventive maintenance program creates documentation that shows systematic maintenance — which matters both in audits and when challenging violations.
Monitor your SMS profile monthly. Check your scores at ai.fmcsa.dot.gov/SMS each month. Violations appear within 30–60 days of an inspection. The sooner you identify a problem area, the sooner you can correct it.
Frequently Asked Questions
Violations remain in the SMS calculation for 24 months with time-weighted severity — meaning they count less as they age. However, violations stay in FMCSA’s Motor Carrier Management Information System (MCMIS) and the Pre-Employment Screening Program (PSP) database much longer. The 24-month window applies specifically to SMS score calculation, not to the underlying records.
Yes. The Crash Indicator tracks crash involvement regardless of fault. However, FMCSA’s crash preventability program allows carriers and drivers to request a determination of whether a crash was preventable. A “not preventable” determination can be used to provide context during audits and negotiations with shippers, though it does not automatically remove the crash from the SMS calculation.
DataQs is FMCSA’s system for requesting a review of roadside inspection data or crash records that you believe are inaccurate. You can submit a request at dataqs.fmcsa.dot.gov. The request goes to the relevant state agency for review. If the challenge is sustained, FMCSA corrects or removes the record from your SMS profile.
A compliance review is a formal investigation of your carrier conducted by an FMCSA safety investigator. It can be triggered by poor CSA scores, a serious accident, a complaint, or as part of FMCSA’s new entrant program. The investigator reviews your records — DQ files, drug testing documentation, HOS records, maintenance records — and evaluates your compliance rating. Outcomes range from a satisfactory rating to a conditional or unsatisfactory rating, which can affect your operating authority.
No. Operating under an out-of-service order is a federal violation. A vehicle OOS order means the vehicle cannot move until the deficiency is corrected and the order is cleared. A driver OOS order means that driver cannot operate any commercial vehicle until the HOS or documentation issue is resolved.
